Costco has hiked the price of its Kirkland Signature synthetic motor oil to nearly twice what members paid for years and imposed strict purchase limits, a direct consequence of Middle East conflict choking the global supply of base oils refined from crude.
A 10-quart case of Kirkland Signature full synthetic motor oil now lists at $57.99 on Costco's website, Fox Business reported. For much of the past several years, that same case sold for roughly $30 to $35. The product page states the purchase limit in bold: two cases per week.
Costco also capped purchases of Mobil 1 full-synthetic motor oil. A 1-quart six-pack is listed at about $44, with a limit of five per membership. FOX Business reached out to Costco for comment but received no response.
Synthetic motor oil depends on Group III base oils refined from crude. Industry analysts say a significant share of the Group III base oils used in the United States is imported from Persian Gulf producers. About 44 percent of normal U.S. demand for Group III base oil was previously supplied from the Persian Gulf before war-related disruptions, the New York Post reported.
Andrew Lipow, president of Lipow Oil Associates, described the supply chain breakdown in specific terms:
"What we do know is that Qatar, UAE, and Korea provide what is known as Group III Base Oils. They are used in synthetic motor oil and synthetic blends of motor oil and have superior performance qualities."
Lipow confirmed the shortage is already working its way through the distribution chain. Packaging plants felt the squeeze first, he said, followed by retailers.
"Yes, there seems to be a supply shortfall, and the packaging plants are seeing it first followed by some of the retailers."
Damage to Shell's Pearl facility in Qatar, which had supplied roughly 30,000 barrels of base oil per day, has removed a major source from the market. Relief is not expected until new domestic Group III production capacity comes online around 2027, according to the Post's reporting. That leaves American consumers facing at least another year of tight supply and elevated prices on a product most vehicle owners need every few months.
Costco members are already adapting to rising costs across the store. Some have turned to butchering their own steaks to offset climbing beef prices, a sign that price-conscious shoppers are feeling the squeeze well beyond the motor oil aisle.
Brent Crude exceeded $109 per barrel on Monday morning. In early July, it sat below $72. That 50-plus percent spike in raw crude has cascaded through every petroleum-derived product, from gasoline to diesel to the base oils that go into every quart of synthetic motor oil on the shelf.
Fuel prices tell the same story. The national average for a gallon of regular gasoline stood at nearly $4.32, according to AAA, up from $4.08 a month ago and $3.18 a year ago. Diesel hit even harder: the national average reached $6.23 per gallon on Monday, up from $5.90 just a week earlier. Diesel had already crossed the $6 mark the previous Friday.
Uncertainty over whether diplomacy will restore normal oil shipments through the Strait of Hormuz, the narrow waterway through which much of the world's crude and refined petroleum products travel, hangs over the market with no resolution in sight.
The Washington Examiner noted that Costco's actions illustrate how supply chain pressures from energy market instability are hitting consumer goods pricing and availability at major retailers. The price increase and rationing are attributed directly to rising costs driven by global energy market disruptions.
Walmart, Amazon, and AutoZone also sell motor oil, but whether any of them have raised prices or imposed purchase limits remains unclear. No confirmed actions by those retailers appeared in available reporting. If the base oil shortage persists into 2027 as projected, it would be unusual for Costco to remain the only retailer forced to ration.
Costco's motor oil rationing is the latest in a series of pressures on the warehouse retailer and its members. The company has also faced scrutiny from the Department of Justice over pricing data as part of a broader antitrust probe, and members have voiced frustration over changes to benefits like the disappearance of Costco Next storefronts.
For the millions of Americans who change their own oil to save money, a near-doubling in price and a hard cap on quantity is not a minor inconvenience. It is a direct tax imposed not by Congress but by conflict half a world away, and by an energy policy that left the country dependent on foreign producers for a basic industrial input.
When the supply of something as ordinary as motor oil can be cut in half by a war overseas, the vulnerability speaks for itself.